GEOHAZARD IN FREETOWN

By Ing. OBA DAVIES GEOHAZARD IN FREETOWN

• Overview of Freetown • What is Geohazard • Geohazard events within Freetown and Contributing Factors • How can we mitigate geohazard • Institutional Capacity to tackle geohazard • SLIE Contribution GEOHAZARD IN FREETOWN

Overview of Freetown Map of Freetown GEOHAZARD IN FREETOWN

• Freetown Municipality - urban population was 772 873 according to the Census made in 2004 and published in 2006 • In 2008, population estimated at approximately 1,000,000 on an annual growth Overview rate of 6.5%, • Estimated at 1,055,964 @ 2015 Census of • Current population growth rate is just over 2% and will peak in year 2020 at 2.14% • Population increase, uncontrolled development Freetown - resulted in reclaiming land in coastal areas & plains; excavate into hilly areas for foundations for houses create unstable slopes - increase siltation and the risk of Uncontrolled Development in the Hills – Leicester Area, 2019 Uncontrolled Development in the Hills – Moyiba Town, 2012 GEOHAZARD IN FREETOWN

• ”Geohazard is the term related to studies and indicates a geomorphological, What is geological, or environmental processes, Geohazard phenomena, and conditions that are potentially dangerous or pose a level of threat to human life, health and property or to the environment."

"Geohazards include sub-aerial and submarine processes, such as , volcanic eruptions, , , debris flows, rock-falls and other types of and . Human induced processes may also be considered as geohazards." GEOHAZARD IN FREETOWN

• Activities that trigger Geohazards (Landslide and Geohazard events Flooding) • Rainfall, Erosion, Improper waste / Garbage within Freetown Disposal

. • Topography and Geology

• Occurrence of actual . Geohazard events IMPACT OF SOIL EROSION BY WATER ON THE INFRASTRUCTURE OF FREETOWN

On-site Impacts

Land-Slides: Landslides can have many causes but can only have one trigger IMPACT OF SOIL EROSION BY WATER ON THE INFRASTRUCTURE OF FREETOWN

• Causes of Land-slides • Geological causes • Weathered materials • Permeability contrasts • Material contrasts • Rainfall • Morphological causes • Fluvial erosion • Wave erosion • Erosion of lateral margins • Subterranean erosion • Vegetation change • Erosion IMPACT OF SOIL EROSION BY WATER ON THE INFRASTRUCTURE OF FREETOWN

• Causes of Land-slides contd. • Physical causes • Intense rainfall • Prolonged precipitation • Ground water changes • Soil pore water pressure • Surface runoff • Soil erosion • Human causes • Land use change • Mining • Quarrying • Deforestation • Land use pattern IMPACT OF SOIL EROSION BY WATER ON THE INFRASTRUCTURE OF FREETOWN

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No. of Days with Rain Topographic Elevation of Western Area and Location of the Regent Landslide (shown in red) and the Flooded Areas in Dwazark and Culvert (circled in red). Quarrying of Gabbroic rock for commercialisation of aggregate Site of Charlotte Landslide Flooding at Kroo Bay Slum Dwellings at Kroo Bay Erosion of Stream Bank, Savage Street Bridge Flooding at Pademba Road – Mends Street junction Slope failure and Rock fall (September 2016) along the Regent - Grafton road (Bathurst village) Siltation in road gutters

GEOHAZARD IN FREETOWN

Different Types of Soil movement in Landslide

Shallow slip Failure – FBC Deep Slip Failure – Regent Mount Aureol, 2019 Landslide , 2017 Landslide Area Mapped Over a Qualitative Hazard Map Erosion along stream bed – Regent landslide area GEOHAZARD IN FREETOWN

Flooding at SLRA Compound

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White water stream to FBC

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Road Erosion around Culvert

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Fourah Bay Road

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• LAWS, Policies and Regulations Mitigation • Acts, regulations and policies are adequate of Road • Overlapping of responsibilities in some Acts Geohazard • Strict enforcement is required where road geohazards can be mitigated GEOHAZARD IN FREETOWN

• DESIGNS • Modern methods for slope Mitigation protection are not considered in road designs of Road • Slope protection designs also provides beautification of the Geohazard roads • SLRA should develop a design standard for slopes along road alignment GEOHAZARD IN FREETOWN

• Sensitization and Education • Communities needs to be sensitize Mitigation and properly educated on the adverse effect of road geohazards of Road • Media communications, jingles Geohazard and local authorities can be useful • Actions and decisions of today are crucial for the future GEOHAZARD IN FREETOWN

• A Big Challenge • There is no documented framework for Capacity management of road geohazards • SLRA has personnel and some equipment to to tackle respond to road geohazard but no structure • FCC has no definite framework; only respond as and when need arises regarding road Geohazard geohazards. Has a structure for garbage clearing and disposal events • Other institutions e.g. EPA and SLP have no clear operational direction towards road geohazard GEOHAZARD IN FREETOWN

• Institutional set-up (Office of National Security) Capacity • The Office of National Security to tackle (ONS) coordinates all forms of emergencies in recent times Geohazard • They are responsible for control and licensing of private Security events Companies (National Security and Central Intelligence Act – 2002) GEOHAZARD IN FREETOWN

• Institutional set-up (Sierra Leone Roads Authority) Capacity • Generally, manage all roads related activities to tackle • Reactive action to road geohazards Geohazard emergency situation as deemed fit • Proactive measures for routine events maintenance (drainage clearing) based on available funding GEOHAZARD IN FREETOWN

• Institutional set-up (Environmental Protection Capacity Agency) • Taken proactive action towards to tackle geohazard after August 2017 landslide Geohazard • Conducting studies on potential events hazard areas • Map out disaster prone areas within Freetown GEOHAZARD IN FREETOWN

• Institutional set-up (Sierra Capacity Leone Police) • Provides support to ONS and to tackle other institutions Geohazard • Traffic diversion and control • Secure lives and properties events where needed GEOHAZARD IN FREETOWN

• Institutional set-up (Freetown City Council) • Responsible for the Freetown Capacity municipality • Coordinates relief items in geohazard to tackle emergency situations Geohazard • supervised general cleaning and clearing of garbage/waste and events disposal • Have a standing contract with MASADA GEOHAZARD IN FREETOWN

• Institutional set-up (Road Maintenance Fund Capacity Administration) • Responsible to manage and administer to tackle the fund • Source funds for road maintenance Geohazard activities - from RUC on fuel, Vehicle License & Registration fees, Investment, events donations or grants, any other sources allocated • Effectively monitor the use of monies allocated from the fund GEOHAZARD IN FREETOWN

• Institutional set-up (Private Institutions) Capacity • Example MASADA contracted by to tackle FCC for garbage collection and disposal Geohazard • Construction companies are contracted for road maintenance events activities (Drainage clearing, premix patching, etc) by SLRA GEOHAZARD IN FREETOWN

• Relevant Data (e.g. Meteorological, Studies / Capacity Research, Design) • Meteorological department unable to to tackle give public alert • Non-existence of Weather & Geohazard Environmental data locally for approx 30 years events • Modern methods for slope protection are not considered in road designs • Research/ studies are not done for data collection by key institutions GEOHAZARD IN FREETOWN

• Stand-alone Institution Capacity • Set up a geohazard risk management centre in the to tackle Ministry of Transport and Aviation Geohazard • setting-up a road geohazard risk management department within events the organization structure of SLRA GEOHAZARD IN FREETOWN

• Funding for resilient Capacity Infrastructure against Geohazards to tackle • No specific budgetary provisions exist within institutional budget of MDAs. Geohazard • Other operational contingencies are used in cases of emergencies events • Ministry of Finance provides funds to address emergency situation to institution(s) GEOHAZARD IN FREETOWN

• Funding for resilient Infrastructure against Capacity Geohazards contd. to tackle • Government usually calls on donor agencies for support Geohazard • ONS may rally round private companies; locally operating INGOs/NGOs and events regional / world institutions for support • Individuals sometimes make contributions based on public appeal GEOHAZARD IN FREETOWN

• Biennial conference (2016) - The theme SLIE “ Risk Management and Contribution Preparedness: an Engineering Perspective for Resilience”

• Setting up a National Communication Centre for the interception and dissemination of early warning information concerning hazards • Establishing an Emergency Operation Center (EOC) Some views for prompt response to any emergency situation • To transform the Disaster Management expressed at the Department (DMD) of the Office of National conference Security (ONS) into a statutory agency, in order to ensure effective coordination and management of disasters • Engineers have not been used for their expertise. GEOHAZARD IN FREETOWN SUMMARY Adapted from: SIERRA LEONE ENGINEERS "DISASTROUS TO EXCLUDE US FROM THE DISASTER MANAGEMENT“ by Ing. A. Keili

• Sierra Leone experiences recurring natural hazards - meteorological hazards (tropical storm thunder and lightning) and Hydrological hazards (landslide, flooding and erosion). • Manmade disasters (e.g. deforestation, coastal sand mining, artisanal aggregate mining) • The hazards are climate related – also having impacts to all terrestrial, wetland and coastal ecosystems. GEOHAZARD IN FREETOWN SUMMARY Adapted from: SIERRA LEONE ENGINEERS "DISASTROUS TO EXCLUDE US FROM THE DISASTER MANAGEMENT“ by Ing. A. Keili • Recent natural disasters indicated the country's vulnerability to • Previous urban development is on the flat land adjacent to the coast • Recent urban developments are spreading up the steep hillsides - construction of houses in an unplanned manner • Stop continuation of practices that may induce geohazards or subjected to strict monitoring and control. • Increases the vulnerability to landslides and other geohazards GEOHAZARD IN FREETOWN SUMMARY Adapted from: SIERRA LEONE ENGINEERS "DISASTROUS TO EXCLUDE US FROM THE DISASTER MANAGEMENT“ by Ing. A. Keili

• Engineers should be fully involve in the phases of disaster mitigation, prevention, preparedness, response, and recovery if Sierra Leone is to meaningfully address problems of natural disaster management and mitigate the risk of geohazards. GEOHAZARD IN FREETOWN